Apologies for not understanding all the new tech, but I figured if anyone could help it would be folks reading this board.
I recently bought a Belkin N+ wireless router to upgrade from the older Linksys G. I have always just used the router and had my devices connect from the factory wireless included in the PS3 as well as my computers which include Mac, Vista, XP, and soon W7.
The upgrade to N+ router didn't exactly eliminate all the hiccups when streaming video or music, and I still encounter disconnects for the computer which is connecting two floors above the Belkin N+ Router.
If the PS3 is on one floor, the N+ Router on another floor, and one essential computer on yet another floor (3 floors), what are my options for improving performance? I am not entirely clear on how a product such as the Belkin Wireless N+ 802.11n USB Adapter actually works, and if it would improve the performance of either or both my computer, or the PS3 which now streams all my video and media.
Any relevant tips and advice are appreciated, thanks.

I'd set the router for 'N' only service and obtain 'N' adapters for all devices that connect. Works well here where mixed 'G' & 'N' did not.
Thanks. There are way too many products on the market and it is impossible to know who to trust. Netgear offers an extender, others offer adapters, but I don't know if I buy an adapter, if I am not just buying redundant equipment instead of improving the signal and bandwidth.
Okay, this is a very hard thing to deal with, you have too much space there. For one, the PS3 is G only, even the slim, not sure why Sony did this, but they did. Wireless G is subject to the slighest interference, the doorbell, microwave, etc... Trying to stream while the kid is making Hot Pockets in the kitchen nuker just doesn't work so well most of the time.
I can go into a hundred different ways to try, but I am only going to talk about what worked for me. It is called BPL, or broadband over powerline. I tried everything wireless, and nothing worked. I bought an N adapter for the PS3 with a Dual Band Router, still had problems (the dual band on the N side would have worked great had Sony used an N card). I was at BB one day and they had a set of Belkin powerline adapters on sale, so I said what the heck, if they don't work, take them back. I don't like Belkin products as I have mostly Linksys gear, but I wouldn't trade these in for nothing. Always a great connection, always working, and streaming is about as good as it gets.
Maybe worth a try? One just connects to router, the other to PS3 and its great, at least for me it solved all my problems. And hey, if it doesn't work, just return the items and someone else gets the open box discount! You will also be able to connect all your other devices wireless as this only takes up a port on the router itself and everything else works as it did before. I am actually going to buy another couple of adapters because it seems they are disappearing just like all great tech that actually works.